WASHINGTON — A fight over how to respond to soaring diesel prices is dividing President Donald Trump’s Republican coalition, with farm-state lawmakers demanding limits on exports and oil companies warning that such a move could worsen fuel costs. Diesel reached a record national average of $6.51 per gallon Monday, according to figures cited by the administration. Agriculture Secretary Brooke Rollins said Trump called her to discuss the increases and that officials across the administration were working on possible responses. “I’ve certainly worked to make sure that the cause and concern of our farmers and ranchers, especially in that area right now, with the cost of diesel and fuel overall, they understand that’s a priority,” Rollins said at a briefing. She said an announcement on potential action could come soon. The pressure is particularly strong in farm states, where diesel is a major expense for planting, harvesting and transporting crops. Sen. Chuck Grassley of Iowa said high prices were “KILLING FARMERS INCOME” and urged Trump to halt diesel exports, invoking export restrictions used by presidents in the 1970s. Rep. Ashley Hinson, also an Iowa Republican and a candidate for the Senate, called for using every available option, including a temporary export suspension and a pause in the federal gas tax. Louisiana Gov. Jeff Landry, a Republican whose state has a large refining and petroleum-export sector, also called for a 90-day diesel export ban. He paired that proposal with a request to make a small-refinery exemption permanent. The administration, however, said Monday that it was not considering an export ban or other restrictions at that time. Energy Secretary Chris Wright has argued that limiting exports could force refineries to reduce their operations because refineries produce diesel alongside gasoline and jet fuel. “If you start putting barriers on flows, pretty quickly you will reduce the production,” Wright said at a recent event. “You’ll have less supply. We need more supply, not less supply.” Mike Sommers, president and CEO of the American Petroleum Institute, made a similar case. He said restricting access to overseas buyers could quickly fill storage facilities along the Gulf Coast and force refineries to cut production. That, he argued, could leave consumers, farmers and the broader economy with less diesel, gasoline and jet fuel. The dispute is politically sensitive because oil and gas producers have traditionally been important allies of the Trump administration, while agricultural interests carry considerable weight among Republican voters. Energy consultant Kevin Book said that when the interests of farmers and oil companies conflict, political leaders typically favor agriculture. Some oil executives with ties to the White House said the administration appeared increasingly concerned about pump prices ahead of the November midterm elections. One executive said officials still understood the risks of an export ban but that pressure to act had intensified. Tom Pyle, president of the fossil-fuel advocacy group American Energy Alliance, called the proposal especially damaging for Louisiana and said it would not resolve high diesel prices. The price increases come as wars and attacks on energy infrastructure disrupt international fuel markets. Trump has blamed attacks by Ukraine on Russian refineries for contributing to the diesel spike, while fuel flows through the Strait of Hormuz have also been constrained by the war involving Iran. Russia is expected to extend its own diesel export restrictions beyond the end of September, when they were scheduled to expire. The United States exported about 1.6 million barrels of diesel during the week of Sept. 11, nearly twice the roughly 850,000 barrels exported during the same week a year earlier, according to the Energy Information Administration. Domestic diesel inventories rose slightly the following week but remained 13% below the five-year average. For farmers and other diesel-dependent businesses, the immediate concern is the cost of operating equipment and moving goods. For policymakers, the challenge is whether a measure aimed at increasing domestic supply would instead disrupt refinery operations, tighten supplies of multiple fuels and push costs higher for households and industries already facing elevated prices.